[0001] The invention relates to a method and apparatus for processing a poultry carcass
part comprising a back portion and two legs connected to said back portion wherein
the legs can eventually be separated from the back portion. The known apparatus for
executing such method comprises a conveyor line with shackles for conveying a series
of poultry carcass parts suspended from the shackles, and at least one cutting device
for making an incision in the joints connecting the legs to the back portion. After
making the incision the legs can be torn loose from the back portion.
[0002] Throughout the years the industry has made efforts to increase the yield of meat
on the legs that are separated from the back portion.
[0003] US 4,639,975 (priority 1984) already had as objective to separate the leg with the oyster remaining
on top thereof and not on the back part of the bird which is less suitable for consumption.
It applied leg guides and cutting knives attached to the guide edges.
[0004] EP-B-0 369 544 (priority 1988) provided better yield by improving the accuracy of the incision by
gripping the back portion of the carcass by a gripping member proceeding in a closed
conveyor loop at higher speeds than the overhead conveyor for the poultry carcasses,
and by application of guide means to guide the back portion of the carcasses until
after the back has been removed from the thighs.
[0005] US 5,176,563 (priority 1990) worked on the incision. As a result of the groin incision, a large
part of the tissue connections between body part and legs remain intact. It proposed
to position the carcass part relative to the incision means and making a groin incision
between the legs and the body part at the side of the legs facing the body part. Following
that the legs were dislocated from the joints and pulled off the body part.
[0006] US 5,188,559 (priority 1991) proposed to reliably and cleanly separate the backs from the legs
of the poultry carcasses and leave the oysters of the joints attached to the separated
ends of the thighbones. For this purpose a first pair of incisions were made at the
locations of the thigh joins, the back portion of the carcass was rotated relative
to the legs for dislodging the ball from the sockets of the thigh joints, and the
back portion of the carcass was pulled away from the legs at the location of the thigh
joints.
[0007] US 6,322,438 (priority 1999) tried to improve the yield of meat on the legs by a more accurate
guiding of the poultry carcasses to the cutters which cut through the tissue extending
between the thighs and the back portions of the carcasses.
[0008] US 2005/0059334 (priority 2003) improves the yield of the meat on the legs by a combination of hold
down bars, guide members, blades, and plowing members to effect a yield value increase
for the whole leg by increasing the amount of flesh and skin removed from the back
portion and left attached to the upper thigh portion of the whole leg.
[0009] The picture that transpires from the prior art during the last decades is that the
problem of improving the yield of meat on the leg that is separated from a back portion
has remained unsolved, despite all the efforts that numerous inventors have spent
during these decades to solve this problem. An apparent problem for increasing this
yield of meat is the accuracy with which the incision can be made at the location
of the joints connecting the legs to the back portion of the poultry carcass part.
[0010] It is therefore a first objective to improve this accuracy. The second objective
is to improve the yield of meat on the legs separated from the back portion of the
poultry carcass part. The third objective is to improve the reliability by which the
yield of meat on the legs can be enhanced. The fourth objective is to attain the aforesaid
objectives whilst maintaining and preferably increasing the processing speed and capacity
of the processing apparatus.
[0011] These and other objectives and advantages are provided by an apparatus and method
according to one or more of the appended claims.
[0012] In a first aspect of the invention the apparatus for processing a poultry carcass
part comprising a back portion and two legs connected to said back portion wherein
the legs are to be separated from the back portion, comprises a conveyor line with
shackles for conveying a series of poultry carcass parts suspended from the shackles,
and is provided with a series of cutting devices that are assembled at the outer circumference
of a cylindrical processing machine which is rotatable around a central body axis.
[0013] Contrary to the apparatus of the invention, all prior art machines are embodied as
linear machines, that means machines in which the poultry carcass parts are conveyed
linearly and processing of the poultry carcass parts is done by immovably positioned
cutting devices. The cutting devices according to the prior art may either have fixed
cutting edges or may be embodied as rotary knives, yet in all cases the poultry carcass
parts are moving past these cutting devices. The consequence thereof is that the accuracy
of making incisions at the joints of the legs is impaired by the natural variation
in the dimensions of the passing poultry carcass parts. To accommodate for this the
conventional linear machines are in a way self adjusting, but this provides another
accuracy problem when two or more poultry carcass parts are processed simultaneously,
which is indeed what happens in practice. Processing of one poultry carcass part adversily
affects the accuracy of processing the other poultry carcass parts.
[0014] The apparatus of the invention differentiates from the prior art by providing for
each poultry carcass part individual cutting devices that are provided at the outer
circumference of a rotating cylindrical processing machine which are operated on the
poultry carcass parts while these poultry carcass parts move along the outer circumference
of said cylindrical processing machine. This construction provides accuracy to the
incision making and also enables high production rates.
[0015] Using a cylindrical processing machine with individual cutting devices for the poultry
carcass parts that are to be processed, provides the notable advantage that prior
to the operation of any one of the cutting devices on a poultry carcass part the shackles
and the back portion of the concerning poultry carcass part can be individually fixed
in position, avoiding interference between neighboring carcass parts that are being
processed.
[0016] To promote the objectives of the invention the cylindrical processing machine is
preferably provided with a series of first fixing means for fixing the carcass back
portions in position. Further it is desirable that the cylindrical processing machine
is provided with a series of second fixing means for fixing the shackles in position.
[0017] In a further aspect of the invention each of the first fixing means and/or second
fixing means is accompanied by cutting devices whereby the cutting devices and said
first fixing means and/or second cutting means are arranged to execute operations
attuned to each other.
[0018] The apparatus of the invention can be suitably arranged such that the first fixing
means comprise a back rest and a hingeable portion that is movable to and fro the
back rest wherein the back portion of the poultry carcass part can be clampingly received
between the back rest and the hingeable portion.
[0019] Further desirably each of the second fixing means is arranged to move the two branches
of any shackle sideways apart from each other. In this way it is possible that prior
to the operation of any one of the cutting devices on a poultry carcass part, the
legs of such poultry carcass part are moved sideways to dislocate said legs from the
joints connecting the legs to the back portion.
[0020] For fixing the shackles in position it is preferred that the branches of the shackles
are provided with receptacles and that the second fixing means are embodied as movable
with protrusions that are dimensioned to engage and fit into said receptacles.
[0021] The apparatus is further suitably embodied such that the cutting devices are movable
up-and-down for providing an incision in the joints connecting the legs to the back
portion. Preferably the up-and-down movement of the cutting devices is enabled after
the shackles and the back portion of the poultry carcass part are fixed in position.
[0022] The invention will hereinafter be further elucidated with reference to the drawing
of an exemplary embodiment which is non-limiting as to the appended claims.
[0023] In the drawing:
- figure 1 shows an isometric view at the cylindrical processing machine of the apparatus
of the invention;
- figure 2A/2B shows a frontal view and side view respectively of a poultry carcass
part arriving at one of the cutting devices provided at the circumference of the cylindrical
processing machine;
- figure 3A/3B shows the fixing into position of the branches of a shackle in a frontal
view and side view respectively;
- figure 4A/4B shows the fixing into position of the carcass back portion in a frontal
view and side view respectively;
- figure 5A/5B shows the upward movement of the cutting device after fixing of the shackle
and the carcass back portion is complete in a frontal view and side view respectively;
- figure 6A/6B shows the cutting operation of the cutting device in a frontal view and
side view respectively.
[0024] Whenever in the figures the same reference numerals are applied, these numerals refer
to the same parts.
[0025] With reference first to figure 1 an apparatus 1 is shown for processing a poultry
carcass part 2, comprising a back portion 3 and two legs 4, 5 connected to said back
portion 3 for providing an incision between the legs 4, 5 and the back portion 3 for
their eventual separation. The apparatus 1 comprises a conveyor line 6 with shackles
7 for conveying a series of poultry carcass parts 2 suspended from the shackles 7,
and at least one cutting device 8 for making an incision in the joints connecting
the legs 4, 5 to the back portion 3. As the figure shows the apparatus is embodied
as a cylindrical processing machine 1 and a series of cutting devices are assembled
at the outer circumference of this cylindrical processing machine 1 which is rotatable
around a central body axis 1'.
[0026] As the figures 2A/2B show the cylindrical processing machine 1 is provided with a
series of first fixing means 11, 12 for fixing the carcass back portions 3 in position
and a series of second fixing means 9 for fixing the shackles 7, more in particular
its branches 7', 7" and the legs 4, 5 suspended therefrom in position.
[0027] Turning now to figure 3A/3B it is shown that after the arrival of the poultry carcass
part 2 at the cylindrical processing machine 1, the second fixing means 9 is arranged
to move the two branches 7', 7" of the shackle 7 of said poultry carcass part 2 in
a direction sideways apart from each other as illustrated with arrows a. The figures
3A/3B show that the branches 7', 7" of the shackles 7 are to this end provided with
receptacles 10 and the second fixing means 9 are embodied as movable protrusions that
are dimensioned to engage and fit into said receptacles 10. The sideways movement
of the protrusions 9 taking with them the branches 7', 7" of the shackles 7 results
in a corresponding sideways movement of the legs 4, 5 and causes the dislocation of
the legs 4, 5 out of their corresponding joints that connect the legs to the back
portion 3 of the poultry carcass part 2.
[0028] Figure 4A/4B shows the situation after fixing of the branches 7', 7" of the shackle
7 into position which is hereabove illustrated with reference to figure 3A/3B. Arrived
at that point in the processing of the poultry carcass part 2, it is shown in figure
4A/4B that the first fixing means 11, 12 comprising a back rest 11 and a hinge-able
portion 12 which is movable to and fro the back rest 11 is operated so as to cause
that the back portion 3 of the poultry carcass part 2 is clampingly received between
the back rest 11 and the hingeable portion 12. Arrow b represents the movement of
the hingeable portion 12 towards the back rest 11 to effectuate the clamping of the
back portion 3 of the poultry carcass part 2. When the movement of the hingeable portion
12 has stopped and the back portion 3 is fixed in position, the cutting device 8 can
become operational, which is shown in figure 5A/5B.
[0029] Figure 5A/5B shows that the cutting device 8 is movable up-and-down, wherein the
upward movement represented by arrow c is for providing an incision in the joints
connecting the legs 4, 5 to the back portion 3. After the incision is made which is
shown in figure 6A/6B, the cutting device 8 may move down again. It is superfluous
to show this downward movement in the figures but the above discussion of the sequence
of first fixing the branches 7', 7" of the shackle 7 at a position in which the legs
4, 5 are dislocated from the joints connecting the legs to the back portion 3, and
the subsequent fixing of the back portion 3 illustrates that the cutting device 8
and said first fixing means 11, 12 and second fixing means 9 are arranged to execute
operations attuned to each other. The up-and-down movement of the cutting device 8
is thus enabled after the shackles 7 and the back portion 3 of the poultry carcass
part 2 are fixed in position.
1. An apparatus (1) for processing a poultry carcass part (2) comprising a back portion
(3) and two legs (4, 5) connected to said back portion (3) wherein the legs (4, 5)
can be separated from the back portion (3), said apparatus (1) comprising a conveyor
line (6) with shackles (7) for conveying a series of poultry carcass parts (2) suspended
from the shackles (7), and at least one cutting device (8) for making an incision
in the joints connecting the legs (4, 5) to the back portion (3), characterized in that a series of cutting devices (8) are assembled at the outer circumference of a cylindrical
processing machine (1) which is rotatable around a central body axis.
2. An apparatus according to claim 1, characterized in that the cylindrical processing machine (1) is provided with a series of first fixing
means (11, 12) for fixing the carcass back portions (3) in position.
3. An apparatus according to claim 2, characterized in that the first fixing means (11, 12) comprise a back rest (11) and a hingeable portion
(12) that is movable to and fro the back rest (11) wherein the back portion (3) of
the poultry carcass part (2) can be clampingly received between the back rest (11)
and the hingeable portion (12).
4. An apparatus according to any one of the previous claims, characterized in that the cylindrical processing machine (1) is provided with a series of second fixing
means (9) for fixing the shackles (7) in position.
5. An apparatus according to claim 4, characterized in that each of the second fixing means (9) is arranged to move the two branches (7', 7")
of any shackle (7) sideways apart from each other.
6. An apparatus according to claim 4 or 5, characterized in that the branches (7', 7") of the shackles (7) are provided with receptacles (10) and
the second fixing means (9) are embodied as movable protrusions (9) that are dimensioned
to engage and fit into said receptacles (10).
7. An apparatus according to any one of claims 2-6, characterized in that each of the first fixing means (11, 12) and/or second fixing means (9) is accompanied
by cutting devices (8) and the cutting devices (8) and said first fixing means (11,
12) and/or second fixing means (9) are arranged to execute operations attuned to each
other.
8. An apparatus according to any one of the previous claims, characterized in that the cutting devices (8) are movable up-and-down for providing an incision in the
joints connecting the legs (4, 5) to the back portion (3).
9. An apparatus according to claim 8, characterized in that the up-and-down movement of the cutting devices (8) is enabled after the shackles
(7) and the back portion (3) of the poultry carcass part (2) are fixed in position.
10. A method for processing a poultry carcass part (2) comprising a back portion (3) and
two legs (4, 5) connected to said back portion (3) for separating the legs (4, 5)
from the back portion (3), wherein a series of poultry carcass parts (2) that are
suspended from shackles (7) are conveyed in a conveyor line (6), and wherein at least
one cutting device (8) is operated for making an incision in the joints connecting
the legs (4, 5) to the back portion (3), characterized in that a series of cutting devices (8) provided at the outer circumference of a rotating
cylindrical processing machine (1) are operated on the poultry carcass parts (2) while
these poultry carcass parts (2) move along the outer circumference of said cylindrical
processing machine (1).
11. The method according to claim 10, characterized in that prior to the operation of a cutting device (8) on a poultry carcass part (2) the
shackles (7) and the back portion (3) of the concerning poultry carcass part (2) are
fixed in position.
12. The method according to claim 10 or 11, characterized in that prior to the operation of a cutting device (8) on a poultry carcass part (2) the
legs (4, 5) of such poultry carcass part (2) are moved sideways to dislocate said
legs (4, 5) from the joints connecting the legs (4, 5) to the back portion (3).